Some have noticed that we use "corn dog" instead of "corny dog."
There are a few good (and at least one rather pointless) reasons for this. As far as we understand things, corny dog is part of the Fletcher's brand and corn dog refers to the object in general. Before either of these, there was a "korn dog," though no one can pin down the invention of--and therefore proper phrase for--the crusty beast.
So we prefer to think of corny dogs like Champagne and corn dogs sparkling wine. Unless certain of terroir, we'll just stick with the latter.
That's one explanation. Of course, there is another matter.
Sometime around the age of 8, saying "corny dog" begins to seem childish. Now that we're chronological adults, we're pretty sure mentioning the phrase causes shrinkage.